1
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Yoshioka E, Imoto Y, Yamaoka Y, Ikeda T, Takahashi H, Tanaka R, Hayashi N, Miyabe H. Intramolecular Cyclopropanation of Active Methylene Derivatives Based on FeCl 2 or FeCl 3-Promoted Radical-Polar Crossover Reactions. Chemistry 2024; 30:e202400602. [PMID: 38658317 DOI: 10.1002/chem.202400602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 04/26/2024]
Abstract
Radical-polar crossover reactions were studied for the intramolecular cyclopropanation of active methylene derivatives. In the presence of FeCl3 as a stoichiometric oxidant and K2HPO4 as a base, the dehydrogenative cyclopropanation of active methylenes proceeded through the FeCl3-promoted oxidative radical cyclization followed by the ionic cyclization to give the bicyclic cyclopropanes. The use of α-chloro-active methylenes leads the subcatalytic cyclopropanation involving two redox pathways. In the presence of K2HPO4, the redox cyclopropanation proceeded by using FeCl2 (20 mol%) in combination with ligand (20 mol%).
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Affiliation(s)
- Eito Yoshioka
- School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan
| | - Yuuki Imoto
- School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan
| | - Yousuke Yamaoka
- School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan
| | - Tomoko Ikeda
- School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan
| | - Hiroki Takahashi
- School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan
| | - Ryousuke Tanaka
- School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan
| | - Naoki Hayashi
- School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan
| | - Hideto Miyabe
- School of Pharmacy and Department of Pharmacy, Hyogo Medical University Minatojima, Chuo-ku, Kobe, 650-8530, Japan
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2
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Ogo S, Yatabe T, Miyazawa K, Hashimoto Y, Takahashi C, Nakai H, Shiota Y. Cyclopropanation Using Electrons Derived from Hydrogen: Reaction of Alkenes and Hydrogen without Hydrogenation. JACS AU 2024; 4:1615-1622. [PMID: 38665645 PMCID: PMC11040560 DOI: 10.1021/jacsau.4c00098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/05/2024] [Accepted: 03/11/2024] [Indexed: 04/28/2024]
Abstract
Have you ever imagined reactions of alkenes with hydrogen that result in anything other than hydrogenation or hydrogenative C-C coupling? We have long sought to develop not only hydrogenation catalysts that activate H2 as hydride ions but also electron transfer catalysts that activate H2 as a direct electron donor. Here, we report the reductive cyclopropanation of alkenes using an iridium electron storage catalyst with H2 as the electron source without releasing metal waste from the reductant. We discuss the catalytic mechanism with selectivity to give the trans-isomer. These findings are based on the isolation of three complexes and density functional theory calculations.
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Affiliation(s)
- Seiji Ogo
- Department
of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- International
Institute for Carbon-Neutral Energy Research (WPI Academy I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- Center
for Small Molecule Energy, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Takeshi Yatabe
- Department
of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- International
Institute for Carbon-Neutral Energy Research (WPI Academy I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- Center
for Small Molecule Energy, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Keishi Miyazawa
- Department
of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- International
Institute for Carbon-Neutral Energy Research (WPI Academy I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yunosuke Hashimoto
- Department
of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- International
Institute for Carbon-Neutral Energy Research (WPI Academy I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Chiaki Takahashi
- Department
of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- International
Institute for Carbon-Neutral Energy Research (WPI Academy I2CNER), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hidetaka Nakai
- Department
of Energy and Materials, Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Osaka 577-8502, Japan
| | - Yoshihito Shiota
- Institute
for Materials Chemistry and Engineering, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
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3
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Fürstner A. How to Break the Law:
trans
‐Hydroboration and
gem
‐Hydroboration of Alkynes. Isr J Chem 2023. [DOI: 10.1002/ijch.202300004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Affiliation(s)
- Alois Fürstner
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
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4
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Tan YX, Li S, Song L, Zhang X, Wu YD, Sun J. Ruthenium-Catalyzed Geminal Hydroborative Cyclization of Enynes. Angew Chem Int Ed Engl 2022; 61:e202204319. [PMID: 35596681 DOI: 10.1002/anie.202204319] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Indexed: 12/25/2022]
Abstract
Disclosed here is the first geminal (gem-) hydroborative cyclization of enynes. Different from known hydroborative cyclizations, this process adds hydrogen and boron to the same position, leading to a new reaction mode. With [Cp*RuCl]4 as catalyst, a range of gem-hydroborated bicyclic products bearing a cyclopropane unit could be rapidly assembled from simple enyne substrates. Control experiments and density functional theory (DFT) calculations provided important insights into the reaction mechanism. Notably, two major competing pathways may operate with substrate-dependence. 1,6-Enynes favor initial oxidative cyclometalation to form a ruthenacyclopentene intermediate prior to engaging hydroborane, while other enynes (e.g., 1,7-enynes) that lack strong propensity toward cyclization prefer initial alkyne gem-(H,B)-addition to form an α-boryl ruthenium carbene followed by intramolecular olefin cyclopropanation. This process also represents the first ruthenium-catalyzed enyne hydroborative cyclization.
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Affiliation(s)
- Yun-Xuan Tan
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Shijia Li
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.,Shenzhen Bay Laboratory, Shenzhen, 518055, China
| | - Lijuan Song
- School of Science, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Xinhao Zhang
- Shenzhen Bay Laboratory, Shenzhen, 518055, China.,Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Yun-Dong Wu
- Shenzhen Bay Laboratory, Shenzhen, 518055, China.,Lab of Computational Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen, 518055, China
| | - Jianwei Sun
- Department of Chemistry and the Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration & Reconstruction, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
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5
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Radkowski K, Fürstner A. A Sphingolipid Fatty Acid Constituent Made by Alkyne trans‐Hydrogenation: Total Synthesis of Symbioramide. Adv Synth Catal 2022. [DOI: 10.1002/adsc.202200540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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6
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Biberger T, Nöthling N, Leutzsch M, Gordon CP, Copéret C, Fürstner A. An Anionic Dinuclear Ruthenium Dihydrogen Complex of Relevance for Alkyne
gem
‐Hydrogenation. Angew Chem Int Ed Engl 2022; 61:e202201311. [PMID: 35363926 PMCID: PMC9322539 DOI: 10.1002/anie.202201311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Indexed: 11/12/2022]
Abstract
During an investigation into the fate of ruthenium precatalysts used for light‐driven alkyne gem‐hydrogenation reactions with formation of Grubbs‐type ruthenium catalysts, it was found that the reaction of [(IPr)(η6‐cymene)RuCl2] with H2 under UV‐irradiation affords an anionic dinuclear σ‐dihydrogen complex, which is thermally surprisingly robust. Not only are anionic σ‐complexes in general exceedingly rare, but the newly formed species seems to be the first example lacking any structural attributes able to counterbalance the negative charge and, in so doing, prevent oxidative insertion of the metal centers into the ligated H2 from occurring.
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Affiliation(s)
- Tobias Biberger
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | - Nils Nöthling
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | - Markus Leutzsch
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | - Christopher P. Gordon
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Christophe Copéret
- Department of Chemistry and Applied Biosciences, ETH Zürich Vladimir-Prelog-Weg 1–5 8093 Zürich Switzerland
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
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7
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Charge-regulated regioselective mechanism of bicobalt-catalyzed hydrogermylation of alkynes: DFT investigation. MOLECULAR CATALYSIS 2022. [DOI: 10.1016/j.mcat.2022.112379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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8
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Tan YX, Li S, Song L, Zhang X, Wu YD, Sun J. Ruthenium‐Catalyzed Geminal Hydroborative Cyclization of Enynes. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Yun-Xuan Tan
- Hong Kong University of Science and Technology School of Science Department of Chemistry HONG KONG
| | - Shijia Li
- Hong Kong University of Science and Technology School of Science Department of Chemistry HONG KONG
| | - Lijuan Song
- Harbin Institute of Technology Shenzhen School of Science CHINA
| | - Xinhao Zhang
- Peking University Shenzhen Graduate School Lab of Computational Chemistry and Drug Design CHINA
| | - Yun-Dong Wu
- Peking University Shenzhen Graduate School Lab of Computational Chemistry and Drug Design CHINA
| | - Jianwei Sun
- Hong Kong University of Science and Technology Department of Chemistry Clear Water Bay Hong Kong HONG KONG
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9
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Caló FP, Zimmer A, Bistoni G, Fürstner A. From Serendipity to Rational Design: Heteroleptic Dirhodium Amidate Complexes for Diastereodivergent Asymmetric Cyclopropanation. J Am Chem Soc 2022; 144:7465-7478. [PMID: 35420801 PMCID: PMC9052758 DOI: 10.1021/jacs.2c02258] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
![]()
A heteroleptic dirhodium
paddlewheel complex comprising three chiral
carboxylate ligands and one achiral acetamidate ligand has recently
been found to be uniquely effective in catalyzing the asymmetric cyclopropanation
of olefins with α-stannylated (silylated and germylated) α-diazoacetate
derivatives. A number of control experiments in combination with detailed
computational studies provide compelling evidence that an interligand
hydrogen bond between the −NH group of the amidate and the
ester carbonyl group of the reactive rhodium carbene intermediate
plays a quintessential role in the stereodetermining transition state.
The penalty for distorting this array outweighs steric arguments and
renders two of the four conceivable transitions states unviable. Based
on this mechanistic insight, the design of the parent catalyst is
revisited herein: placement of appropriate peripheral substituents
allows high levels of diastereocontrol to be imposed upon cyclopropanation,
which the original catalyst lacks. Because the new complexes allow
either trans- or cis-configured stannylated cyclopropanes to be made
selectively and in excellent optical purity, this transformation also
marks a rare case of diastereodivergent asymmetric catalysis. The
products are amenable to stereospecific cross coupling with aryl halides
or alkenyl triflates; these transformations appear to be the first
examples of the formation of stereogenic quaternary carbon centers
by the Stille reaction; carbonylative coupling is also achieved. Moreover,
tin/lithium exchange affords chiral lithium enolates, which can be
intercepted with a variety of electrophilic partners. The virtues
and inherent flexibility of this new methodology are illustrated by
an efficient synthesis of two salinilactones, extremely scarce bacterial
metabolites with signaling function involved in the self-regulatory
growth inhibition of the producing strain.
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Affiliation(s)
| | - Anne Zimmer
- Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr D-45470, Germany
| | - Giovanni Bistoni
- Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr D-45470, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr D-45470, Germany
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10
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Biberger T, Nöthling N, Leutzsch M, Gordon CP, Copéret C, Fürstner A. An Anionic Dinuclear Ruthenium Dihydrogen Complex of Relevance for Alkyne gem‐Hydrogenation. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202201311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Tobias Biberger
- Max-Planck-Institut für Kohlenforschung: Max-Planck-Institut fur Kohlenforschung Organometallc Chemistry 45470 Mülheim/Ruhr GERMANY
| | - Nils Nöthling
- Max-Planck-Institut für Kohlenforschung: Max-Planck-Institut fur Kohlenforschung Chemical Crystallography 45470 Mülheim/Ruhr GERMANY
| | - Markus Leutzsch
- Max-Planck-Institut für Kohlenforschung: Max-Planck-Institut fur Kohlenforschung NMR Spectroscopy 45470 Mülheim/Ruhr GERMANY
| | - Christopher P. Gordon
- ETH Zürich: Eidgenossische Technische Hochschule Zurich Inorganic Chemistry 8093 Zürich SWITZERLAND
| | - Christophe Copéret
- ETH Zürich: Eidgenossische Technische Hochschule Zurich Inorganic Chemistry 8093 Zürich SWITZERLAND
| | - Alois Fürstner
- Max-Planck-Institut fur Kohlenforschung Organometallic Chemistry Kaiser-Wilhelm-Platz 1 45470 Mülheim/Ruhr GERMANY
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11
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Peil S, Gutiérrez González A, Leutzsch M, Fürstner A. C-H Insertion via Ruthenium Catalyzed gem-Hydrogenation of 1,3-Enynes. J Am Chem Soc 2022; 144:4158-4167. [PMID: 35170941 PMCID: PMC8915261 DOI: 10.1021/jacs.1c13446] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
![]()
gem-Hydrogenation of an internal alkyne with the
aid of [Cp*RuCl]4 as the precatalyst is a highly unorthodox
transformation, in which one C atom of the triple bond is transformed
into a methylene group, whereas the second C atom gets converted into
a ruthenium carbene. In the case of 1,3-enynes bearing a propargylic
steering substituent as the substrates, the reaction occurs regioselectively,
giving rise to vinyl carbene complexes that adopt interconverting
η1/η3-binding modes in solution;
a prototypical example of such a reactive intermediate was characterized
in detail by spectroscopic means. Although both forms are similarly
stable, only the η3-vinyl carbene proved kinetically
competent to insert into primary, secondary, or tertiary C–H
bonds on the steering group itself or another suitably placed ether,
acetal, orthoester, or (sulfon)amide substituent. The ensuing net
hydrogenative C–H insertion reaction is highly enabling in
that it gives ready access to spirocyclic as well as bridged ring
systems of immediate relevance as building blocks for medicinal chemistry.
Moreover, the reaction scales well and lends itself to the formation
of partly or fully deuterated isotopologues. Labeling experiments
in combination with PHIP NMR spectroscopy (PHIP = parahydrogen induced
polarization) confirmed that the reactions are indeed triggered by gem-hydrogenation, whereas kinetic data provided valuable
insights into the very nature of the turnover-limiting transition
state of the actual C–H insertion step.
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Affiliation(s)
- Sebastian Peil
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | | | - Markus Leutzsch
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
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12
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Biberger T, Hess SN, Leutzsch M, Fürstner A. Hydrogenative Cycloisomerization and Sigmatropic Rearrangement Reactions of Cationic Ruthenium Carbenes Formed by Catalytic Alkyne
gem
‐Hydrogenation. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202113827] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Tobias Biberger
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | - Stephan N. Hess
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | - Markus Leutzsch
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
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13
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Biberger T, Hess SN, Leutzsch M, Fürstner A. Hydrogenative Cycloisomerization and Sigmatropic Rearrangement Reactions of Cationic Ruthenium Carbenes Formed by Catalytic Alkyne gem-Hydrogenation. Angew Chem Int Ed Engl 2021; 61:e202113827. [PMID: 34911159 PMCID: PMC9306539 DOI: 10.1002/anie.202113827] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Indexed: 11/10/2022]
Abstract
gem‐Hydrogenation of propargyl alcohol derivatives with [CpXRu(MeCN)3]PF6 (CpX=substituted cyclopentadienyl) as catalysts affords cationic pianostool ruthenium carbene complexes which are so electrophilic that they attack a tethered olefin to furnish cyclopentene products; cyclopropanation or metathesis do not compete with this novel transformation. If the transient carbenes carry appropriate propargylic substituents, however, they engage in ([2,3]‐sigmatropic) rearrangements to give enol esters (carbonates, carbamates, sulfonates) or alkenyl halides. Both pathways are unprecedented in the vast hydrogenation literature. The proposed mechanistic scenarios are in line with labeling experiments and spectroscopic data; most notably, PHIP NMR spectroscopy (PHIP=parahydrogen induced polarization) provides compelling evidence that the reactions are indeed triggered by highly unorthodox gem‐hydrogenation events.
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Affiliation(s)
- Tobias Biberger
- Max-Planck-Institut für Kohlenforschung: Max-Planck-Institut fur Kohlenforschung, Organometallic Chemistry, GERMANY
| | - Stephan N Hess
- Max-Planck-Institut für Kohlenforschung: Max-Planck-Institut fur Kohlenforschung, Organometallic Chemistry, GERMANY
| | - Markus Leutzsch
- Max-Planck-Institut für Kohlenforschung: Max-Planck-Institut fur Kohlenforschung, NMR Spectroscopy, GERMANY
| | - Alois Fürstner
- Max-Planck-Institut fur Kohlenforschung, Organometallic Chemistry, Kaiser-Wilhelm-Platz 1, 45470, Mülheim/Ruhr, GERMANY
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14
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Melot R, Saiegh TJ, Fürstner A. Regioselective trans-Hydrostannation of Boron-Capped Alkynes. Chemistry 2021; 27:17002-17011. [PMID: 34240757 PMCID: PMC9291331 DOI: 10.1002/chem.202101901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Indexed: 01/16/2023]
Abstract
Alkynyl‐B(aam) (aam=anthranilamidato) derivatives are readily available bench‐stable compounds that undergo remarkably selective reactions with Bu3SnH in the presence of [Cp*RuCl]4 as the catalyst. The addition follows a stereochemically unorthodox trans‐selective course; in terms of regioselectivity, the Bu3Sn‐ unit is delivered with high fidelity to the C‐atom of the triple bond adjacent to the boracyclic head group (“alpha,trans‐addition”). This outcome is deemed to reflect a hydrogen bonding interaction between the protic −NH groups of the benzo‐1,3,2‐diazaborininone ring system and the polarized [Ru−Cl] bond in the loaded catalyst, which locks the substrate in place in a favorable orientation relative to the incoming reagent. The resulting isomerically (almost) pure gem‐dimetalated building blocks are amenable to numerous downstream functionalizations; most remarkable is the ability to subject the −B(aam) moiety to Suzuki‐Miyaura cross coupling without need for prior hydrolysis while keeping the adjacent Bu3Sn‐ group intact. Alternatively, the tin residue can be engaged in selective tin/halogen exchange without touching the boron substituent; the fact that the two ‐NH entities of −B(aam) do not protonate organozinc reagents and hence do not interfere with Negishi reactions of the alkenyl halides thus formed is another virtue of this so far underutilized boracycle. Overall, the ruthenium catalyzed trans‐hydrostannation of alkynyl‐B(aam) derivatives opens a practical gateway to isomerically pure trisubstituted alkenes of many different substitution patterns by sequential functionalization of the 1‐alkenyl‐1,1‐heterobimetallic adducts primarily formed.
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Affiliation(s)
- Romain Melot
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
| | - Tomas J Saiegh
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim an der RuhrMülheim/Ruhr, Germany
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15
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Zachmann RJ, Fürstner A. Light-Driven gem Hydrogenation: An Orthogonal Entry into "Second-Generation" Ruthenium Carbene Catalysts for Olefin Metathesis. Chemistry 2021; 27:7663-7666. [PMID: 33871083 PMCID: PMC8251631 DOI: 10.1002/chem.202101176] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Indexed: 01/11/2023]
Abstract
The newly discovered light-driven gem hydrogenation of alkynes opens an unconventional yet efficient entry into five-coordinate Grubbs-type ruthenium carbene complexes with cis-disposed chloride ligands. Representatives of this class featuring a chelate substructure formed by an iodo-substituted benzylidene unit react with (substituted) 2-isopropoxystyrene to give prototypical "second-generation" Grubbs-Hoveyda complexes for olefin metathesis. The new approach to this venerable catalyst family is safe and versatile as it uses a triple bond rather than phenyldiazomethane as the ultimate carbene source and does not require any sacrificial phosphines.
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Affiliation(s)
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
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16
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Peil S, Bistoni G, Goddard R, Fürstner A. Hydrogenative Metathesis of Enynes via Piano-Stool Ruthenium Carbene Complexes Formed by Alkyne gem-Hydrogenation. J Am Chem Soc 2020; 142:18541-18553. [PMID: 33073575 PMCID: PMC7596760 DOI: 10.1021/jacs.0c07808] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
The
only recently discovered gem-hydrogenation
of internal alkynes is a fundamentally new transformation, in which
both H atoms of dihydrogen are transferred to the same C atom of a
triple bond while the other position transforms into a discrete metal
carbene complex. [Cp*RuCl]4 is presently the catalyst of
choice: the resulting piano-stool ruthenium carbenes can engage a
tethered alkene into either cyclopropanation or metathesis, and a
prototypical example of such a reactive intermediate with an olefin
ligated to the ruthenium center has been isolated and characterized
by X-ray diffraction. It is the substitution pattern of the olefin
that determines whether metathesis or cyclopropanation takes place:
a systematic survey using alkenes of largely different character in
combination with a computational study of the mechanism at the local
coupled cluster level of theory allowed the preparative results to
be sorted and an intuitive model with predictive power to be proposed.
This model links the course of the reaction to the polarization of
the double bond as well as to the stability of the secondary carbene
complex formed, if metathesis were to take place. The first application
of “hydrogenative metathesis” to the total synthesis
of sinularones E and F concurred with this interpretation and allowed
the proposed structure of these marine natural products to be confirmed.
During this synthesis, it was found that gem-hydrogenation
also provides opportunities for C–H functionalization. Moreover,
silylated alkynes are shown to participate well in hydrogenative metathesis,
which opens a new entry into valuable allylsilane building blocks.
Crystallographic evidence suggests that the polarized [Ru–Cl]
bond of the catalyst interacts with the neighboring R3Si
group. Since attractive interligand Cl/R3Si contacts had
already previously been invoked to explain the outcome of various
ruthenium-catalyzed reactions, including trans-hydrosilylation,
the experimental confirmation provided herein has implications beyond
the present case.
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Affiliation(s)
- Sebastian Peil
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Giovanni Bistoni
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Richard Goddard
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470 Mülheim/Ruhr, Germany
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17
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Biberger T, Zachmann RJ, Fürstner A. Grubbs Metathesis Enabled by a Light-Driven gem-Hydrogenation of Internal Alkynes. Angew Chem Int Ed Engl 2020; 59:18423-18429. [PMID: 32608043 PMCID: PMC7589215 DOI: 10.1002/anie.202007030] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/19/2020] [Indexed: 02/02/2023]
Abstract
[(NHC)(cymene)RuCl2 ] (NHC=N-heterocyclic carbene) complexes instigate a light-driven gem-hydrogenation of internal alkynes with concomitant formation of discrete Grubbs-type ruthenium carbene species. This unorthodox reactivity mode is harnessed in the form of a "hydrogenative metathesis" reaction, which converts an enyne substrate into a cyclic alkene. The intervention of ruthenium carbenes formed in the actual gem-hydrogenation step was proven by the isolation and crystallographic characterization of a rather unusual representative of this series carrying an unconfined alkyl group on a disubstituted carbene center.
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Affiliation(s)
- Tobias Biberger
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
| | | | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
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18
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Biberger T, Zachmann RJ, Fürstner A. Grubbs Metathesis Enabled by a Light‐Driven
gem
‐Hydrogenation of Internal Alkynes. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202007030] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Tobias Biberger
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | | | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
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19
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Padín D, Varela JA, Saá C. Cp*RuCl-Vinyl Carbenes: Two Faces and the Bifunctional Role in Catalytic Processes. Chemistry 2020; 26:7470-7478. [PMID: 32134145 DOI: 10.1002/chem.202000391] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Indexed: 11/07/2022]
Abstract
Ruthenium vinyl carbenes derived from Cp/Cp*RuCl-based complexes (Cp=cyclopentadiene, Cp*=1,2,3,4,5-pentamethylcyclopentadiene) have been routinely invoked as key intermediates in tandem reactions involving a carbene/alkyne metathesis (CAM). A priori, these intermediates resemble the Grubbs-type family of catalysts, but they exhibit a completely different reactivity pattern that few, if any, other catalytic system can reproduce so far. The reactivity of these species with α-unsubstituted and α-substituted alkynals showcases the peculiarities of these intermediates. Although Z-vinyl dihydrooxazines are preferentially obtained with the former, Z-vinyl epoxypyrrolidines are obtained with the latter. A combination of spectroscopic and computational data now prove that a η3 -coordination mode of the ruthenium vinyl carbene and the presence of a Lewis basic chloride ligand give rise to two markedly different stereoelectronic faces, which are responsible for the unconventional reactivity of these species.
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Affiliation(s)
- Damián Padín
- Centro Singular de Investigación en Química Biolóxica e, Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - Jesús A Varela
- Centro Singular de Investigación en Química Biolóxica e, Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
| | - Carlos Saá
- Centro Singular de Investigación en Química Biolóxica e, Materiais Moleculares (CiQUS), Departamento de Química Orgánica, Universidade de Santiago de Compostela, 15782, Santiago de Compostela, Spain
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20
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Caló FP, Fürstner A. A Heteroleptic Dirhodium Catalyst for Asymmetric Cyclopropanation with α‐Stannyl α‐Diazoacetate. “Stereoretentive” Stille Coupling with Formation of Chiral Quarternary Carbon Centers. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202004377] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Fabio P. Caló
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
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21
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Caló FP, Fürstner A. A Heteroleptic Dirhodium Catalyst for Asymmetric Cyclopropanation with α-Stannyl α-Diazoacetate. "Stereoretentive" Stille Coupling with Formation of Chiral Quarternary Carbon Centers. Angew Chem Int Ed Engl 2020; 59:13900-13907. [PMID: 32426901 PMCID: PMC7496581 DOI: 10.1002/anie.202004377] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/18/2020] [Indexed: 01/06/2023]
Abstract
The heteroleptic dirhodium paddlewheel catalyst 7 with a chiral carboxylate/acetamidate ligand sphere is uniquely effective in asymmetric [2+1] cycloadditions with α‐diazo‐α‐trimethylstannyl (silyl, germyl) acetate. Originally discovered as a trace impurity in a sample of the homoleptic parent complex [Rh2((R)‐TPCP)4] (5), it is shown that the protic acetamidate ligand is quintessential for rendering 7 highly enantioselective. The ‐NH group is thought to lock the ensuing metal carbene in place via interligand hydrogen bonding. The resulting stannylated cyclopropanes undergo “stereoretentive” cross coupling, which shows for the first time that even chiral quarternary carbon centers can be made by the Stille–Migita reaction.
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Affiliation(s)
- Fabio P Caló
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung, 45470, Mülheim/Ruhr, Germany
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22
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Murai M, Taniguchi R, Takai K. Cyclization of 1,n-Enynes Initiated by the Addition Reaction of gem-Dichromiomethane Reagents to Alkynes. Org Lett 2020; 22:3985-3988. [DOI: 10.1021/acs.orglett.0c01304] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Masahito Murai
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
- Department of Chemistry, Graduate School of Science, Nagoya University, Furo, Chikusa, Nagoya 464-8602, Japan
| | - Ryuji Taniguchi
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Kazuhiko Takai
- Division of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
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23
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Koley S, Altman RA. Recent Advances in Transition Metal-Catalyzed Functionalization of gem-Difluoroalkenes. Isr J Chem 2020; 60:313-339. [PMID: 32523163 PMCID: PMC7286626 DOI: 10.1002/ijch.201900173] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 02/17/2020] [Indexed: 11/11/2022]
Abstract
gem-Difluorinated alkenes are readily accessible building blocks that can undergo functionalization to provide a broad spectrum of fluorinated and non-fluorinated products. Herein, we review recent (since 2017) transition metal-catalyzed transformations of these specialized alkenes and summarize general reactivity patterns of these reactions. Many transition metal-catalyzed reactions undergo net C-F bond functionalization reactions to deliver monofluorinated products. These reactions typically proceed through β-fluoro alkylmetal intermediates that readily eliminate a β-fluoride to deliver monofluoroalkene products. A second series of reactions exploit coinage metal fluorides to add F- to the gem-difluorinated alkene, and further functionalization delivers trifluoromethyl-containing products. In stark contrast, few transition metal-catalyzed reactions proceed in net "fluorine-retentive processes" to deliver difluoromethylene-based products.
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Affiliation(s)
- Suvajit Koley
- Department of Medicinal Chemistry, The University of Kansas, 1251 Wescoe Hall Drive, Lawrence, Kansas, 66045, USA
| | - Ryan A Altman
- Department of Medicinal Chemistry, The University of Kansas, 1251 Wescoe Hall Drive, Lawrence, Kansas, 66045, USA
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24
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Wang HX, Wan Q, Low KH, Zhou CY, Huang JS, Zhang JL, Che CM. Stable group 8 metal porphyrin mono- and bis(dialkylcarbene) complexes: synthesis, characterization, and catalytic activity. Chem Sci 2020; 11:2243-2259. [PMID: 32180931 PMCID: PMC7047983 DOI: 10.1039/c9sc05432d] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 12/30/2019] [Indexed: 12/17/2022] Open
Abstract
Alkyl-substituted carbene (CHR or CR2, R = alkyl) complexes have been extensively studied for alkylcarbene (CHR) ligands coordinated with high-valent early transition metal ions (a.k.a. Schrock carbenes or alkylidenes), yet dialkylcarbene (CR2) complexes remain less developed with bis(dialkylcarbene) species being little (if at all) explored. Herein, several group 8 metal porphyrin dialkylcarbene complexes, including Fe- and Ru-mono(dialkylcarbene) complexes [M(Por)(Ad)] (1a,b, M = Fe, Por = porphyrinato dianion, Ad = 2-adamantylidene; 2a,b, M = Ru) and Os-bis(dialkylcarbene) complexes [Os(Por)(Ad)2] (3a-c), are synthesized and crystallographically characterized. Detailed investigations into their electronic structures reveal that these complexes are formally low-valent M(ii)-carbene in nature. These complexes display remarkable thermal stability and chemical inertness, which are rationalized by a synergistic effect of strong metal-carbene covalency, hyperconjugation, and a rigid diamondoid carbene skeleton. Various spectroscopic techniques and DFT calculations suggest that the dialkylcarbene Ad ligand is unique compared to other common carbene ligands as it acts as both a potent σ-donor and π-acceptor; its unique electronic and structural features, together with the steric effect of the porphyrin macrocycle, make its Fe porphyrin complex 1a an active and robust catalyst for intermolecular diarylcarbene transfer reactions including cyclopropanation (up to 90% yield) and X-H (X = S, N, O, C) insertion (up to 99% yield) reactions.
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Affiliation(s)
- Hai-Xu Wang
- State Key Laboratory of Synthetic Chemistry , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China .
| | - Qingyun Wan
- State Key Laboratory of Synthetic Chemistry , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China .
| | - Kam-Hung Low
- State Key Laboratory of Synthetic Chemistry , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China .
| | - Cong-Ying Zhou
- State Key Laboratory of Synthetic Chemistry , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China .
- College of Chemistry and Materials Science , Jinan University , Guangzhou , China
| | - Jie-Sheng Huang
- State Key Laboratory of Synthetic Chemistry , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China .
| | - Jun-Long Zhang
- Beijing National Laboratory for Molecular Sciences , College of Chemistry and Molecular Engineering , Peking University , Beijing , China
| | - Chi-Ming Che
- State Key Laboratory of Synthetic Chemistry , Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , China .
- HKU Shenzhen Institute of Research & Innovation , Shenzhen , China
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25
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Buchsteiner M, Martinez‐Rodriguez L, Jerabek P, Pozo I, Patzer M, Nöthling N, Lehmann CW, Fürstner A. Catalytic Asymmetric Fluorination of Copper Carbene Complexes: Preparative Advances and a Mechanistic Rationale. Chemistry 2020; 26:2509-2515. [PMID: 31916634 PMCID: PMC7065061 DOI: 10.1002/chem.202000081] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Indexed: 01/21/2023]
Abstract
The Cu-catalyzed reaction of substituted α-diazoesters with fluoride gives α-fluoroesters with ee values of up to 95 %, provided that chiral indane-derived bis(oxazoline) ligands are used that carry bulky benzyl substituents at the bridge and moderately bulky isopropyl groups on their core. The apparently homogeneous solution of CsF in C6 F6 /hexafluoroisopropanol (HFIP) is the best reaction medium, but CsF in the biphasic mixture CH2 Cl2 /HFIP also provides good results. DFT studies suggest that fluoride initially attacks the Cu- rather than the C-atom of the transient donor/acceptor carbene intermediate. This unusual step is followed by 1,2-fluoride shift; for this migratory insertion to occur, the carbene must rotate about the Cu-C bond to ensure orbital overlap. The directionality of this rotatory movement within the C2 -symmetric binding site determines the sense of induction. This model is in excellent accord with the absolute configuration of the resulting product as determined by X-ray diffraction using single crystals of this a priori wax-like material grown by capillary crystallization.
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Affiliation(s)
| | | | - Paul Jerabek
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
- Present Address: Nanotechnology DepartmentHelmholtz-Zentrum Geesthacht21502GeesthachtGermany
| | - Iago Pozo
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
| | - Michael Patzer
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
| | - Nils Nöthling
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
| | | | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
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26
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Peil S, Fürstner A. Mechanistic Divergence in the Hydrogenative Synthesis of Furans and Butenolides: Ruthenium Carbenes Formed by gem-Hydrogenation or through Carbophilic Activation of Alkynes. Angew Chem Int Ed Engl 2019; 58:18476-18481. [PMID: 31609498 PMCID: PMC6916381 DOI: 10.1002/anie.201912161] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Indexed: 01/15/2023]
Abstract
Enynes with a tethered carbonyl substituent are converted into substituted furan derivatives upon hydrogenation using [Cp*RuCl]4 as the catalyst. Paradoxically, this transformation can occur along two distinct pathways, each of which proceeds via discrete pianostool ruthenium carbenes. In the first case, hydrogenation and carbene formation are synchronized ("gem-hydrogenation"), whereas the second pathway comprises carbene formation by carbophilic activation of the triple bond, followed by hydrogenative catalyst recycling. Representative carbene intermediates of either route were characterized by X-ray crystallography; the structural data prove that the attack of the carbonyl group on the electrophilic carbene center follows a Bürgi-Dunitz trajectory.
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Affiliation(s)
- Sebastian Peil
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung45470Mülheim/RuhrGermany
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27
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Peil S, Fürstner A. Mechanistic Divergence in the Hydrogenative Synthesis of Furans and Butenolides: Ruthenium Carbenes Formed by
gem
‐Hydrogenation or through Carbophilic Activation of Alkynes. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201912161] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Sebastian Peil
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung 45470 Mülheim/Ruhr Germany
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28
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Longobardi LE, Fürstner A. trans
‐Hydroboration of Propargyl Alcohol Derivatives and Related Substrates. Chemistry 2019; 25:10063-10068. [DOI: 10.1002/chem.201902228] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 06/07/2019] [Indexed: 01/04/2023]
Affiliation(s)
- Lauren E. Longobardi
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim/Ruhr Germany
| | - Alois Fürstner
- Max-Planck-Institut für Kohlenforschung Kaiser-Wilhelm-Platz 1 45470 Mülheim/Ruhr Germany
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